PLANTS!! Presented by Ashwana Fricker How do they Interact?

Background Grass: A monocotyledenous green plant in the family Poacaea Forb: Any non-woody flowering plant that is not a grass

Background Facilitative (+/+) –Soil Improvement –Structure –Deter Predators –Attract Pollinators Competitive (-/-) –Water –Nutrients (ex. Nitrogen) –Sunlight Commensalistic (+/0) –Plant secretions Grass: A monocotyledenous green plant in the family Poacaea Forb: Any non-woody flowering plant that is not a grass

Competition: An Argument For There is an increase in nutrients and water infiltration beneath plant canopy, suggesting an increase in the number of forbs in grass clumps

Commensalism: An Argument for C4 Photosynthesis in Blue and Black Grama suggests possible C3 photosynthesis in forbs

Facilitation: An Argument For There may be nutrient retention by forbs –Decreases nutrient leaching (benefits the grasses)

The Question What type of relationship? –Competition (work against each other) –Commensalism (one works for the other) –Facilitation (work with each other)

Methods Quarter meter plots- randomly tossed in Black Grama, Blue Grama, and Ranchland –Veg Surveys: Grass Area - quad Forb Type Forb Area Forb Position

Results

Methods Grasses were clipped in order to determine whether short- term grazing had an effect on forb growth –10 cm radius –Clipped to the base –2 species: caesalpenia drepanocarpa macheranthera pinnatifida

Results

Synopsis There is no strong correlation between grazing and forb growth in a season, but long term data shows that there is an increase in forb number when the grass cover decreases

References Callaway, R., Walker, L.; Ecology (1997); Competition and Facilitation: A Synthetic Approach to Interactions in Plant Communities; pp Kieft, T., White, C., Loftin, S., Aguilar, R., Craig, J., Skaar, D Temporal Dynamics in Soil Carbon and Nitrogen Resources at a Grassland- Shrubland Ecotone. Ecosystems. p Bhark, E., Small E Association between Plant Canopies and the Spatial Patterns of Infiltration in Shrubland and Grassland of the Chihuahuan Desert, New Mexico. Ecosystems. p

Thanks to… Sevilleta LTER Fish and Wildlife Scott Collins Jennifer Johnson The Friggens Michell With help from… Fred Whiteman Andrew Rominger Caitlin Smith Brenda Nieto Alex Benhumea Tierney Adamson